output1 if {
    false           # boolean literal false
}

output2 if {
    1 == 2          # evaluates to false
}

output3 if {
    is_number("a")  # evaluates to false
}

output4 if {
    input.no_such_field        # undefined
}

output5 if {
    0 / 0                      # undefined
}

output6 if {
    to_number("not a number")  # undefined
}
